Process for making yarn packages



March 1938- 1 K. WELLHAMS 2,H,26

PROCESS FOR MAKING YARN PACKAGES Filed Nov. 19, 1935 2 Sheets-Sheet 1 BNVENTOR. W! W///ia'm ATTORNEY.\

March 15, 1938. K7 WELLEAMS 2,23%,926

PROCESS FOR MAKING YARN PACKAGES Filed Nov. 19, 1935 2 Sheets-Sheet 2 /fi/ w 7 ATTORNEY a Patented Mar. 15, 1938 UNITED STATES PATENT OFFICE assignments, to E. I.

du Pont de Nemours &

Company, Wilmington, Del., a corporation of Delaware Application November 19, 1935, Serial No. 50,562

2 Claims.

This invention relates to the production of a shipping package of twisted thread, and more particularly it relates to a method for the pro duction of an improved light weight shipping package of twisted thread by a single win-ding and uptwisting operation, which package will be suitable for direct use in the production of fabrics.

The present invention is particularly applicable to the production of twisted threads of organic derivatives of cellulose, for example, cellulose esters such as cellulose acetate, cellulose propionate, cellulose acetopropionate, cellulose stearate, and cellulose ethers such as ethyl cellulose and benzyl cellulose, in view of the necessary step of heating such twisted yarn in a moist atmosphere to set the twist imparted thereto. The invention will be described in detail with particular reference to cellulose acetate, it being understood that the invention is not to be limited thereto but applies broadly to organic derivatives of cellulose.

Prior to the present invention, a commonly used method of producing shipping packages of twisted cellulose acetate yarn suitable for direct use in the production of fabrics involved the following essential operation:

Cellulose acetate yarn, after spinning, drying and dressing with a finishing composition, was collected on supply bobbins. These supply bobbins were placed on a spindle of an uptwisting machine and uptwisted over the end of the supply bobbin as the latter revolved in a vertical position at a high rate of speed, and onto a rotating wooden receiving spool which rotates at a constant peripheral speed in a horizontal position. The number of twists per inch imparted to the cellulose acetate thread was determined by the ratio of the number of revolutions per minute of the supply bobbin to the wind-up speed of the thread in inches per minute on the receiving bobbin. The wooden receiving bobbins were then placed in a heated, moist atmosphere for a certain period of time for the purpose of setting the twist imparted to the thread. The receiving bobbins were subsequently placed on a winding or coming machine and the twisted threads were unwound from the receiving bobbins and precision Wound onto light pasteboard cones or light weight metallic spools. These light weight cones or spools are suitable for shipping purposes, and due to their being precision wound will permit ready removal of the thread during subsequent textile producing operations.

By the term precision wound as used throughout the specification and claims is meant winding of thread into a package with such smoothness, uniformity and orderliness that the package will remain firm during shipment and the thread will unwind therefrom without tangling, clinging or sloughing.

This procedure necessarily involves two winding operations, namely the winding from the supply bobbin to a receiving spool, and from the receiving spool to the shipping core. This double winding procedure is undesirable due to high handling and operating expense and the requirement of a large amount of floor space and additional equipment and labor. Furthermore, the double Winding results in an unavoidable increase in the number of knots per package of yarn and in aninevitable degradation and lowering of the quality of the yarn because of the additional handling operation.

The shipping of the yarn on the wooden receiving spools would be uneconomical due to the excessive weight of said spools. Thread wound on wooden receiving spools is unsatisfactory for use in the manufacture of textiles due to the susceptibility to breakage of the thread during the unwinding thereof. On the other hand, the use of wooden receiving bobbins has been considered essential heretofore in the production of twisted cellulose acetate thread by reason of their resistance to the heated, moist atmosphere necessary in the setting of the twist of the thread.

It is therefore an object of the present invention to produce, by a single winding and uptwisting operation, shipping packages of twisted cellulose acetate thread in which the twist has been set and which is suitable for direct use in fabrics.

It is a further object of this invention to provide a light weight, receiving bobbin suitable for use as a shipping core and which will withstand the hot, moist atmosphere to which bobbins or spools of twisted cellulose acetate must be subjected to set the twist in the thread.

It is another object of this invention to uptwist and wind a cellulose acetate thread directly into a shipping package which may be subjected to a hot, moist atmosphere for setting of the twist in the thread, and which is precision wound with squared edges and is substantially free of overthrown ends.

Other objects of the invention will appear hereinafter.

The objects of the invention are accomplished in general by up-twisting a cellulose acetate thread from a supply bobbin, collecting said twisted thread by precision winding the same on a headless, cylindrical, light weight core which is impregnated or coated with a material to render it smooth and insensitive to the hot, moist atmosphere necessary for setting the twist in said thread. The precision winding is carried out in such a manner that the traverse of the thread longitudinally of the package is not substantially less than 1.36 inches for each revolution of the thread about the package.

The twisted thread must be wound on a light weight, headless, cylindrical core which is impregnated or coated with a material to render it smooth and insensitive to the heated, moist at mosphere which is necessary for the setting of the twist in the thread for several reasons. The core must be light weight and headless so that the resulting package may be economically shipped to the desired points of destination without adding unnecessarily to the weight of the thread.

The core must be cylindrical so that the package may be wound with precision by a surface drive mechanism and will have uniform density and a minimum of, or no overthrown loops projecting from the ends of the package.

If the core were conical, the resulting package would have irregular hardness or density, poorly formed ends, and many overthrown loops, with the result that the thread would be damaged and degraded. This is due to the fact that the point of contact of the cone with the ,surface drive wheel will shift from one end to the other and consequently the rotational speed of the cone will constantly vary. When the point of contact between the surface drive wheel and the core is at the large end of the cone, the latter will rotate more slowly than when the point of contact is at the small end of the cone.

The core must be impregnated or coated with a protective substance which will render the core insensitive to hot, moist atmosphere used in setting the twist in the thread by reason of the fact that this operation must necessarily be carried. out on the shipping core, to prevent double winding. Furthermore, this coating must be smooth to prevent abrasion or degradation of the yarn.

Such light weight cylindrical cores can be constructed of a great many known materials such as fiber, paper, pasteboard, laminated cloth, and the like. The core is coated or impregnated with a substance which upon drying or other treatment will render the same insensitive to the atmosp.1eric conditions present in the setting of the twist. The core may, for example, be given the well known zinc chloride treatment. Alternatively, the core may be impregnated with a phenolaldehyde resin of the bakelite type or other synthetic or natural resin with or without modifying constituents.

The thread is precision-wound on the core so that the packages will be firm and evenly wound to withstand shipment, and will unwind with facility during the subsequent textile operations. The precision-winding is carried out in such a manner that the traverse of the thread longitudinally of the package is not substantially less than 1.36 inches for each revolution of the thread about the package whereby to prevent sloughing of the thread from the ends of the package and to substantially eliminate over-thrown ends.

It is only by combining these various steps of procedure that a shipping package of the type set forth can be produced with a single winding operation. Although one or more of the detailed steps set forth above may have utility in obtaining a somewhat improved package by the double winding procedure known heretofore, nevertheless, it is only by the functional cooperation of the several steps that a suitable shipping package which is acceptable in the trade, can be produced with a single winding operation.

In adapting conventional uptwisting equipment for use in carrying out the present invention, the conventional receiving take-up spool may be replaced by a wooden spindle having an external diameter of such a size as to form a snug fit with the internal surface of the cylindrical shipping core. r

The construction of the cylindrical shipping core and the wooden spindle will be more clearly apparent by reference to the following detailed description taken in connection with the accompanying illustration in which:

Figure l is a perspective view of a shipping cone constructed in accordance with the invention;

Figure 2 is a perspective view of a wooden spindle constructed in accordance with the present invention.

Figure 3 is a diagrammatic view showing the spinning of cellulose acetate thread and collecting the thread on a supply bobbin;

Figure 4 is a diagrammatic view showing the twisting and precision-winding of cellulose acetate thread from the supply bobbin onto a cylindrical shipping core; and

Figure 5 shows diagrammatically the, removable shipping core mounted on a spindle assembly.

Referring to the drawings, reference numeral ll designates generally the cylindrical shipping core. This core is preferably provided at one end thereof with a groove l2 around which the thread may be wrapped a plurality of turns prior to its being precision-wound on the shipping core. The thread positioned in this groove will function as a tailing which is highly advantageous for continuous operation of textile machinery. Thus, the transfer tail on the first core is tied to the starting thread of the second core before the first shipping core has been unwound and is to be replaced by the second package. The cylindrical core I I, as stated above, is coated or impregnated with a material which will render it impervious to hot, moist atmospheric conditions.

Reference character 13 generally designates the wooden spindle which is preferably provided with groove l4 and springs IS. The springs 16 are adapted to slide within the groove l4 and are anchored in the spindle by means of the leg H. The spindle is furthermore provided with a shaft 15 which is adapted to be mounted in spaced grooves of an up-twisting machine in which they are adapted to be rotated by means of surface drive mechanism in the same manner as is well known with receiving take-up bobbins. Y The springs l6 are adapted to contact with the internal surface of the cylindrical core I I and thereby hold the cylindrical core ll firmly on the wooden spindle is to prevent relative rotation therebetween.

The shipping core and wooden spindle assembly are preferably dynamically balanced so that the take-up core upon which the thread is collected will rotate smoothly to permit precision winding of the thread thereon.

Figure 3 illustrates diagrammatically the spinning and collecting of cellulose acetate thread, a cellulose acetate solution being introduced through supply pipe l8 and spinning nozzle l9 into spinning cell 20, the thread passing around a guide 2i, through an aperture in the spinning cell and being collected as a supply package 22 on supply bobbin 23 mounted on spindle 24. Referring to Figure 4, supply package 22 and supply bobbin 23 are mounted on a spindle 24 of an uptwister, spindle 24 being driven by means of pulley 25 driven by a belt 26. The thread passes through guide 21, being collected onto the removable cylindrical shipping core II mounted on spindle I3 rotating in bearings 28, the precision winding of the twisted thread being effected by means of a traverse guide 29 mounted on traverse bar 30. Shipping core H and spindle assembly I3 are rotated by surface contact with -a drive roll 3| which is suitably driven from an external source of power.

Figure 5 is an end view showing spindle assembly l3 and the removable shipping core H with the twisted, precision-wound yarn thereon, the shipping core being firmly held on the spindle to prevent relative rotation therebetween.

The outstanding advantage of the present invention is the provision of a light weight shipping package of twisted cellulose acetate yarn with a single Winding operation. It is evident that this elimination of the usual coming or spooling step after the twisting operation results in a decided economy and considerable improvement in the quality of the yarn. Furthermore, the invention is applicable to standard up-twisting equipment without the necessity of providing for a costly and time-consuming modification in the equipment.

Obviously, many modifications and changes may be made in the above description without departing from the nature and spirit thereof, and it is therefore to be understood that the invention is not to be limited thereto except as set forth in the appended claims.

I claim:

1. The method of producing a light-weight shipping package of t w i tes d cellulose derivative thread, comprising forming a cellulose derivative thread from a cellulose derivative spinning solution and collecting said thread on a supply bobbin, uptwisting and simultaneously precision winding said thread from said supply bobbin onto a light-weight cylindrical core which is removable from its spindle, said precision winding operation being carried out with a thread traverse longitudinally of the package not substantially less than 1.36 inches for each revolution of the thread about the package.

2. The method of producing a light-weight shipping package of twisted cellulose derivative thread, comprising forming a cellulose derivative thread from a cellulose derivative spinning solution and collecting said thread on a supply bobbin, uptwisting and simultaneously precisionwinding said thread from such supply bobbin onto a smooth light-weight, headless, cylindrical core which is removable from its spindle and which is insensitive to the hot, moist atmosphere necessary for setting the twist in the thread, said precision winding operation being carried out with a thread traverse longitudinally of the package not substantially less than 1.36 inches for each revolution of the thread about the package, and subjecting said twisted thread to atmospheric conditions which are sufficiently hot and moist to set the twist in said thread.

KI WILLIAMS. 

